Electronic tube packet



April 7, 1959 u us 2,881,347 7 ELECTRONIC TUBE PACKET Filed Aug. '31, 1954 I INVENTOR DAVID RUFUS A'n'oait j United States Patent ELECTRONIC TUBE PACKET David Rufus, Long Island City, N.Y., assignor to Sylvania Electric Products Inc., a corporation of Massachusetts Application August 31, 1954, Serial No. 453,232

Claims. (Cl. 313-256) This invention relates to electronic tube packet construction suitable for automatic production and to apparatus for assembling and unifying the parts of the packet.

It is an object of this invention to provide an electron tube packet which shall be compact, rugged in construction so as to give long life, and have reproducible characteristics.

It is a further object of the invention to provide a tube packet construction which shall lend itself toward ease in assembly of electrodes and spacers.

It is yet another object of the invention to provide a simple process for assembling the necessary electrodes and spacers into a mount and for compacting the same into a unified package.

Yet another object of the invention is to provide an apparatus for facilitating manufacture of the packet.

These and other objects will become apparent after reading the following specification in conjunction with the accompanying drawings, in which Fig. 1 is a plan view of a tube mount with parts broken away to expose interior portions.

Fig. 2 is an end view of the packet.

Fig. 3 is a diagrammatic side view of aportion of I apparatus utilized for the production of a mount, parts being shown in section.

Fig. 4 is a sectional view through the apparatus of Fig. 3 taken on the line 4-4 thereof. 7

Fig. 5 is an end view of the apparatus of Fig. 3 looking in the direction of the arrows 5-5 in Fig. 3, and

Fig. 6 is a side view of a cutter employed in the apparatus.

For the purposes of illustration only and for the sake of simplicity, the description has been limited to a triode although it should be understood that the principles of this invention may be applied to tube mounts with any number of electrodes.

The triode mount or packet here illustrated comprises an indirectly heated cathode 10, a pair of grids 1'2 and 14, and an :anode .16, with suitable spacer rods 18 between the elements. The rods 1-8 are of tungsten or the like coated with a .suitableinsulating material an alumina.

. The cathode 10 comprises a metallic sleeve '20, :rect-angular in cross section, in the exemplary form of the invention, with an emissive coating on the outside and withan insulated filamentary typeof heater 22 internally of the sleeve. At one end of the cathode sleeve is welded, as at 24, a pair of Welded together metallic straps 28 of low heat conductivity, these straps being brought together at their ends as illustrated in Fig. '2, with the ends clamped between the insulated rods 18. At the other end, a second pairof straps 26 welded to one another is employed but'these are only form fitted around the cathode to allow for sliding of the sleeve on expansion and contraction'of-th'e samedue to heating and cooling. A suitable tab 30 10 be welded to a stem lead is welded to one end of the sleeve.

The grids are each comprised of a hollow rectangular metallic frame .32, as of copper or molybdenum, with grid ice . 2 wires 34 of tungsten or the like brazed or otherwise se cured to one face of the frame. The frames are so related to the cathode, that the grid wires face the cathode, thespacing between grid wires and the cathode being determined by the diameter of the insulated spacer rods.

The spacer rods 18 each comprise a sheathed metal rod 36 of tungsten, nickel or the like coated, catephoretically, if desired, with an insulating coating 38 such as alumina. With the catephoretic method of coating, it is easily possible to maintain the coating diameter to :.0005 inch, thus making it possible to produce these rods accurately as well as cheaply.

The anode 16 comprises a nickel plate bent to substantially U form with converging free ends 40, as illustrated in Fig. 2, the .free ends being spot welded together as shown at 42 to form a flat packet tightly holding the oathode and grids in position within the anode. The spacer rods 18 maintain suitable spacing between the cathode and grids and between the grids and the anode. The anode is further provided with longitudinal recesses 44 to accommodate the outside rods 18 to position them in the packet and also with very slightly weakened portions 45 to facilitate the forming of the convergent portions of the anode.

The grids and the anode maybe provided with tabs, as is :usual in the art, to connect these parts with stem leads.

There ,is thus provided a simple compact tube mount construction capableof jig or machine production.

The tube mount may be produced very simply in the jig described below.

support is provided having an upstanding irod' guide wall 52 and a horizontal shelf 54. The guide wall is provided with a number of holes with flaring mouths as at 56, the number of holes corresponding to the number of rods 18 to be utilized in the construction of the tube mount and their spacing apart vertically corresponding to the spacing apart vertically of these rods in the finished mount. The horizontalspacing :of the holes, however, is greater than the horizontal spacing of the rods 18 in the finished mounts by an amount sufiicient to allow for the vertical sliding of the required cathode and grids in between the rods.

Adjacent to the wall 52 is located the cutting mechanism shown in side 'view in Fig. 6. This mechanism comprises a ledger blade 60 carried by a horizontal reciprocable operating bar 62. to a position between the rows of holes '56 and along the face of the wall 52. The

mechanism also comprises a pair of vertically spaced apart, horizontal, bevelled cutter blades 64, 66, the lower one of which, 66, rides in a slot 68 cut into the support 50. When these blades are brought into closing relationship with the ledger bar 60, rods 18, which had been threaded through the guide wall 52, will be severed. The cutter blades are provided with parallel link mechanism 70 to cause the blades to approach the ledger bar in parallel sliding fashion to effect a sliding cut .simulta:

neously on .all of the'rods. The mechanism 70 comprises a link 72 pivoted to both blades 64 and 66, a second link 72 also pivoted to both blades 64 and 66, said second link 72 being equal in length to the first link and pivoted centrally at 74 to the operating bar, a pinion 76 pinned at 78 to first link 72 and a stationary rack .80 on which the pinion rolls. A stop arm 82 on the pinion cooperating with stop pins 84, 84, On the bar 62 prevents excessive movement of the cutter blades. After therods have been severed, the operating bar is moved to the right in Fig. 6 to clear the space in front of wall 52. p

The shelf 54 is provided with a rectangular opening86 (see Figs. 3 and 4) of a length less than the long dimension of the grid frames '32 and of a width just a little longer than the spread dimension of the anode 16, as seen in dotted lines in Fig. 3. Also associated with-the shelf is an- L-shaped slidable'tail block 88 having a strap 90 under the shelf. The block is held, in adjusted position, against slidable movement with respect to the shelf by stop pin 91, as shown in Figs. "3 and 5 engaging in suitably spaced recesses in the under face of the shelf. On the rear face of the vertical wall of the block there is a dovetail groove 92 slidably engaging a cooperating clamp operating rod 94. This rod operates the knees of a pair of like toggles 96, the links of which are connected to parallel clamp jaws 98. These jaws are each provided withpins' 100 riding in slots 102 in the tail block to limit the motion of the jaws to rectilinear movement toward and from the rods 18 threaded through holes 104 in the block. The holes in the tail block are in registration with the holes 56 in guide Wall 52. The jaws are effective upon movement of bar 94 to the left in Fig. 5, to clamp the insulated rods 18 to the tail block 88. When the bar 94 is moved to the right, the jaws are moved toward each other and the holes 104 are left unobstructed so that the rods 18 may freely thread themselves therethrough as will be described.

Inthe' operation of the device as thus far described, the rods 18 are threaded through the holes 56 to an extent beyond the rear right hand face of the wall 52. The cutter operating bar 62 is then moved to cutting positionand the cutter blades operated by linear displacement of pinion 76 on stationary rack 80 to cut off the ends of the .rods 18, the rods of course initially being projected.

far enough over the ledger bar 60 so that all bars will extend equally beyond the rear face 52 after cutting. The bar 62 is then operated to withdraw the cutters and the tail block 88 is advanced into contact with wall 52 with the clamp jaws 98 in inoperative position. Since the holes in the tail block register with the holes in wall 52, the rods 18 will thread themselves through the tail block and to an extent to project slightly therebeyond. The clamp jaws are now operated to clamp the rods to the tail block and the tail block is withdrawn to the position shown in Fig. 3, with the spring pressed detent 91 locking the tail block in position. With the rods held tightly by the clamp jaws, the cutter blades are brought into operation and the rods are severed. The rod sections held by the tail clamp 88 are sutficiently rigid, even though they are pliable, to maintain their alignment as determined by the spacing of the holes in the tail block 88.

Above the jig there is suitably supported for conjoint lateral displacement, as viewed in Figs. 4 and 5, a number of chutes 106,108, 110, and 112. The chutes 106 and 108, when positioned as shown in Fig. 5, are in position to guide grid frames 32 with wires thereon into the spaces between the outside and inside coated rods 18. At this time the chute 110 is in position to guide a cathode in between the inner rods 18. Fig. 4 shows the grids and cathode already in place with the chutes shifted preparatory'to forcing an anode 16 over the assembly. It will be noted that the grid frames 32 will be located in between the rods by engagement of the lower edges of the frames with the upper surface of the shelf 54 on opposite sides of th opening 86. So, too, the cathode 10 will be properly located by reason of the straps 26, 28 similarly engaging the top surface of shelf 54. When the chutes are shifted to the positions shown in Fig. 4, an anode 16, performed as shown in Fig. 4, may be forced over the assembly as by being pressed down by a plunger 114 operative through the chute 112. The plunger is depressed sufiiciently to cause the upperrecesses 44 in the anode to snap over the upper outer rods 18.

Means are provided for effecting the compacting of the elements which comprise the mount assembly. These means comprise in part the press cheeks or plates 116, each having an operating rod 118. Recesses 120 are formed in the cheeks to conform to the configurations at 44in the anode. After the anode has been forced into proper vertical downward position and so that the upper rods 18 are seated in the recesses, the plates 116 are simultaneously moved toward each other by suitable mechanism to cause the lower recesses 44 in the anode to embrace the lower outer rods 18, and the whole assembly is compacted, the rods 18 flexing as necessary at their clamped ends to permit parallel approach of the portions of the rods 18 within the confines of the mount assembly. Substantially simultaneously with the movement of the press cheeks 116, a suitable number of pairs of welding rods 122 are caused to approach each other to cause the free edges of the anode to approach each other to form the apex of the anode as shown in Fig. 2. When the free ends of the anodes are fully contacted, a welding shot is passed through the electrodes and anode to eifect spot welding of the anode ends.

After the welding operation, the electrodes are withdrawn as are the press cheeks 116 and the clamp operating rod 94 is operated to release the clamps on the spacing rods 18. The pin 91 is then withdrawn from its recess in shelf 54 and the tail block 88 is retracted so that pin 91 locks in the outer recess of the shelf. The compacted mount assembly may now be removed from the shelf 54 by any suitable means.

The cycle of operation is again started by moving the tail block 88 against the wall 52 and operating the clamps to grip the rods 18, ready for withdrawal of the block 88 from the wall 52.

After removal of the electrode assembly from the jig the filamentary heater and necessary tabs are added.

Having thus described my invention what is claimed is: 1."An electrode assemblycomprising a cathode, a grid on each side of the cathode, an anode envelope surround- I ing the cathode and grids, and insulated spacer rods between the cathode and grids and between the grids and the anode envelope, the envelope tightly holding the parts in assembled relationship, the envelope having a U-shaped cross-section with the free ends of the legs convergent and firmly secured to one another.

2. An electrode assembly comprising a cathode sleeve, at least one strap athwart the sleeve and retaining the sleeve in position with respect to the strap, a grid on a side of the sleeve, an anode envelope surrounding the sleeve and grid, and insulated spacer rods between the strap and the grid and between the grid and the envelope, the envelope tightly holding the parts in assembled relationship. 1

3. An electrode assembly comprising a cathode sleeve, at least one strap athwart the sleeve and retaining the sleeve in position with respect to the strap, a grid on each side of the sleeve, an anode envelope surrounding the sleeve and grids, and insulated spacer rods between the strap and grids and between the grids and envelope, the

I envelope tightly holding the parts in assembled relationship.

4. An electrode assembly comprising a cathode sleeve, straps across the sleeve at spaced locations along the length of the sleeve, one of the straps being immovably secured to the sleeve and the other slidably retaining the sleeve, a grid on a side of the sleeve, an envelope surrounding the grid and sleeve, and insulated spacer rodsbetween the straps and the grid and between the grid and the envelope, the envelope tightly holding the parts in assembled relationship.

5. An electrode assembly comprising a cathode sleeve, straps across the sleeve at spaced locations along the length of the sleeve, one of the straps being immovably U secured to the sleeve and the other slidably retaining the in assembled relationship.

, (References on following page) References Cited in the file of this patent UNITED STATES PATENTS Krol May 25, 1937 Kosack Apr. .16, 1940 Schafer Aug. 5, 1947 Bachman Nov. 2, 1948 Van Der Berge et al Dec. 6, 1949 Diggle Apr. 11, 1950 6 Van Gessel May 23, 1950 Hroch Aug. 7, 1951 Robinson Jan. 8, 1952 Law Ian. 20, 1953 Walsh Nov. 24, 1953 Kovach Feb. 1, 1955 Klopping Aug. 21, 1956 

